Immunity
by Call Me Babykins
Summary: Right. Dean's done this before. At least once. Or had this done to him. Right. That was it. But it's just like eating out a girl. At least he thinks it is. He can do this—no big deal. But he may get more than he's bargained for. Established Wincest. Part of my First Times compilation.
1. Disclaimer

The following is intended for mature audiences. Discretion is advised. Contains graphic anilingus and incest.

Supernatural and its characters belong to Eric Kripke.


	2. Chapter 1

Right. Dean's done this before. At least once. Or had this done to him. Right. That was it. But it's just like eating out a girl. At least he thinks it is.

He can do this—no big deal. And of course he's overthinking and not thinking and thinking in all sorts of confused jumbles.

Thinking Sam's skin looks soft and pink like he's blushing all over. And, God, how pink the tight pucker of his ass is.

Thinking he might have better access to it with Sam on all fours, but that he wants to see Sam's face. That is if he can see past Sam's balls.

Thinking how, with Sam's chest heaving so hard and his neck blushing so deep, he looks as nervous as Dean feels.

Sam's cock gives delicious little twitches every time Dean touches him and even though he's only half-hard, still recovering, he's already leaking precome. Dean licks his lips.

His mouth is dry.

He can do this—no big deal. Did he or did he not fuck Rhonda Hurley while wearing a lacey pair of pink panties after she ate his ass out? You bet your sweet ass he did. This, this is nothing.

Except that it's Sam.

And, because it's Sam, it's everything.

Even Rhonda Hurley was impressed by a bigger than average cock and bravado to match, but Sam's already seen his cock and seen through his bravado and Sam's gonna be a hell of a lot harder to impress.

Anyone else—any guy, any girl, any other piece of ass—it could all go wrong and still be okay. Any other piece of ass could tell him he was the worst lay they ever had and that he was a bastard to boot and, okay, that'd bruise his ego, but he'd move on to the next pair of spread legs.

But this ass is Sam's ass and Sam's ass isn't just some piece of ass. It's a fucking important ass.

And one he wants to stay important for a long time.

"Dean?" Sam's hard again and he's reaching down toward Dean like he's going to tell him that it's okay, that he doesn't have to if he doesn't want to, that Sam doesn't mind, that they can just do something else and _fuck that_.

Even though the pink whorl of Sam's asshole might just be the most intimidating thing Dean's ever seen he's never backed down just because what he's facing is intimidating and he'll be damned if he's going to start now.

He starts with what he knows: laps at Sam's cock, taking just the head into his mouth and tonguing at the slit, at the sticky wet mess there, kisses and sucks Sam's balls, strokes his perineum.

He moves down, kisses the inside of Sam's thigh, pushes Sam's legs apart a little more so he's spread out for Dean.

Oh God.

Sam's breathing shallow and Dean's head is pounding with the prospect of what he's about to do.

Just like eating out a girl, he reminds himself, and presses his face into Sam's ass.

He's sloppy, not really sure where to lick, and a little anxious about how it might taste, what it might feel like, and it's disorienting not having a clit there as a surefire "touch me here," no lips to open and tongue between, but if Sam's soft, heavy panting and how he's clutching at Dean's shoulders, nails biting, is anything to go by it must feel some kind of good.

And it doesn't taste as bad as he was expecting. Actually doesn't taste bad at all. Just like skin—really fucking soft skin like nothing he's ever touched before—and an earthy, deep, Sam taste. And a little like soap, but that's not bad. Just means Sam's all clean.

He draws back a little. Sam's skin is shiny with saliva.

Dean swallows. His lips and one cheek are wet, really wet, wet with his own spit and that makes him feel awkward, self-conscious. "That feel okay?"

"Yeah," the word is a sharp intake of breath. Sam's arms twitch like he wants to pull Dean against him, force Dean's face back into his ass, but he doesn't. Always a gentleman, always looking out for Dean.

Like if Dean said he had to stop right now, this instant, Sam would tell him that was all right, no big deal, but fuck that, he's the one taking care of Sam and the way Sam says, "Jesus, Dean, feels," and the way Sam pauses and licks his lips before he says, "Feels _good_." means there's no stopping Dean.

And, okay, so it's nothing like eating out a girl. There's no slick running down his chin, no hoods or flaps or lips to get his tongue up under, and Sam doesn't have those fucking ridiculous fake nails that leave gouge marks like being mauled by a cat.

It's nothing like eating out a girl—it's so much fucking better. Sam's makes these breathy little moans that catch in his throat halfway out and turn into whimpers and sighs. And, Christ, he's sensitive _everywhere_.

Dean laps at the swell of his perineum, up high enough that Sam's balls, heavy even though he's already come once, rest on his temple for a minute.

That shouldn't be hot, but it kind of is. He can't put a finger on what it is—the intimacy, the exclusiveness of what he's doing, knowing no one else has done this for Sam, or the dirty-nasty-sweet way it feels to have Sam's balls on his face—but, God, it feels good.

He follows Sam's taint back down, making little circles around Sam's entrance and Sam gasps out his name, "Dean. Oh my God, _Dean_," tangling his long fingers in Dean's hair.

Dean can't help how he grins.

He licks long, wet stripes over Sam's center, dipping his tongue in a little when he crosses Sam's entrance. Sam's muscles clench involuntarily and Dean can feel every squeeze.

And, fuck, when he seals his lips around Sam's entrance and _sucks_ Sam bucks upward with a groan that sends a jolt straight to Dean's cock.

He always had to get himself back in the game again after the girls—letting them lick their juice from his mouth while he rubbed himself hard—but when his neck starts to hurt and he lays down, propped up on his elbows, his cock rubs hard on the sheets. Fuck, he's throbbing, aching hard and ready.

And that probably makes perfect sense because he's basically drowning in the taste and scent of Sam's arousal and nothing's ever made him hotter than that, but when it hits him …

Holy Mother of God, when it hits him, it hits him _hard_.

He tries to keep suction, thrusting into Sam's body with his tongue at the same time and Sam's _keening_, arching against the bed.

Sam's never this vocal—not ever, but, damn, it's pressing buttons that Dean didn't even know he had.

He humps the mattress, using his fingers to spread Sam's sphincter, opening him up, stiffening his tongue to press it into Sam. He thrusts slow, as deep as he can get, drinking in the way Sam is moaning, fuck, _whimpering_ and swearing.

He draws back just long enough to direct Sam to touch himself before pushing his tongue as deep into Sam as he can, curling the tip up as he draws it out.

Sam gasps, "Fuck!" It's almost a sob.

He's shaking and Dean can taste the salt of his sweat standing out against his skin.

Dean works his hips against the mattress, the movement automatic, a reaction to the stimulus of the sounds Sam's making, the scent of his sweat, the way he tastes, how soft he is inside.

Christ, Dean's never been this close without direct attention on his cock.

And when Sam comes, breath harsh and choppy, gasping out garbled profanity that sounds somewhere between a prayer and a wail, and his internal muscles _push_ Dean's tongue out of him, Dean nearly comes right along with him.

But he presses back in, working against the clench of Sam's walls, thrusting as deep as he can, as Sam arches under the aftershocks. He grinds against the mattress, losing his rhythm, and when Sam gasps out "Dean," in what is definitely a sob, it's all Dean can do to brace his forehead against Sam's inner thigh as his orgasm hits him like a punch, driving all the breath out of him, as he fucks into the bed.

When he come down his fingernails are digging deep into Sam's flesh, his whole face feels wet with sweat and saliva and maybe even tears. Sam is trembling.

"Dean," he begs, hands on Dean's shoulders, pulling him upward.

They lay next to each other, lined up shoulder to shoulder, panting.

Sam looks over at him, skin bright with tears, but smiling. "Did you—?"

Dean can only nod. He should be embarrassed, coming in the sheets like a kid getting his dick wet for the first time, but he's not sure he's ever come that hard regardless of the circumstances.

He holds Sam's hand. It's still small in his. Sam's done so much growing. Christ, he's almost _grown,_ but he's still so small.

"God, Dean," Sam sighs, leaning over to kiss Dean.

Dean pulls away with a sudden, deep awareness of where his mouth has been. _All_ the places his mouth has been. He feels sick—how many chicks has he done this with? He stopped counting hook ups when he was sixteen. When you kiss you're sharing the saliva of everyone you've ever kissed, right? And probably the germs of everything you've ever licked or sucked or … Fuck.

He's disgusting. Doing this to Sam. Touching Sam like this,_ defiling_ him. Sammy, his sweet, innocent kid brother.

His stomach lurches.

"I gotta brush my teeth,"

He sits up, but Sam's right behind him.

"The fuck you do," Sam grabs him.

"I taste like ass," Dean pushes away from Sam, but the kid wraps his skinny limbs around him and sticks to him like a fucking octopus.

"I've just gotta brush my teeth, I have ass breath!"

"I don't care," Sam presses his lips to Dean's shoulder. "C'mon, Dean, lay down,"

"It'll just take a second, Sam. _Jesus_, you really in such a hurry to taste your own ass?"

Sam clutches even tighter. "If I don't care, you don't have any fucking right to either. It's _my_ ass."

"And it's my goddamn mouth,"

Neither of them move for a second and then Sam lets go. He takes a deep, shuddering breath and, God, Dean knows he's on the verge of tears. It kills him to know how vulnerable Sam must feel.

Fuck. He remembers that feeling. Laying in Rhonda Hurley's bed while she showered, still in her panties, the fabric all wet and sticky and suddenly feeling dirty. Feeling like he's done something to be ashamed of.

But Sam's done nothing to be ashamed of. There's nothing more beautiful, more pure, than Sam the way he is right now—breathing still heavy from his orgasm, fingers still unsure, barely more than a child, but growing up faster than Dean can keep up with.

He's still sitting there; close enough that even though they aren't touching Dean can feel him breathing. Chin practically still tucked over Dean's shoulder.

Dean turns his head as far as it'll go and presses a kiss to the spot near Sam's nose where his lips land.

"Sorry,"

Sam starts to turn for a proper kiss and Dean licks him. Then Sam's sputtering and they're wrestling each other to the bed. He lets Sam win, pin him down, propped up on top of him with his damn sharp elbows digging into Dean's sternum.

Sam looks down. His face his pink—kinda glowy. It's cute.

It's innocent, sweet as ever, somehow immune to Dean's disease.

Sam leans down slow, and kisses him, forcing his mouth open, touching their tongues together deliberately, thoroughly tasting Dean's mouth, biting gently at Dean's lower lip.

And Dean lets him. Because dammit there's nothing better than this, nothing he could ever hope for or dream up, and sure as fuck nothing he's already had.

Just when he's really getting into it, thinking they can probably both get it up for another round, Sam sits up.

He looks down with an expression Dean can't read.

"Why are you such an asshole?"

"If I'm such an asshole why do you put up with me?" The words are out of his mouth before he can stop them. Dammit, he's just an insecure little girl sometimes.

Sam shrugs, stupid fucking elbows digging in. "If I don't, who will?"

"Aw, Sammy, that's sweet," Dean reaches up to pull Sam into another kiss, but the little twat twists out of his grip.

"Uh uh. You taste like ass," Sam grins, ear to ear, face all dimples and self-satisfaction.

"Fuck you!"

"Not before you brush your teeth,"

Sam rolls off and looks over at him expectantly. He's naked as the day he was born, flushed red on his neck and collarbone, little hairs stuck to his face with sweat, eyes big and bright, come dried on his stomach, and, God, he looks like an angel. A smirking punk-ass angel.

"Bitch,"

Sam just smiles wider, if that's possible. "Jerk."

Dean pushes himself off the bed, makes a huge show of stumbling to the bathroom and brushing his teeth.

By the time he gets back Sam's calm, looks half-asleep. He snuggles up close when Dean gets into bed and they kiss soft and slow for a while until Dean's mouth tastes like Sam instead of toothpaste.

Sam comes up for air, eyes still closed, looking sleepy and sweet, eyelashes dark on his cheekbones. He sighs, like he's completely satisfied—as if he has everything in the world and can't think of a single thing he'd add.

Dean's never seen him like this.

Sam turns over and Dean spoons him close as he falls asleep. Sam breathes soft and deep, nestled against Dean.

Right. Well, they're definitely doing that again.


End file.
